You might start with Googlescholar and pubmed, toxnet pretty good too. Start with reviews in these search engines. Organization may be done either by classes of toxin (see Cassarett and Doull) or by methods (chromatographic, bioassays, colorimetic, etc). Who is the audience? That should dictate organization and content.

I agree with Dr. Lucas. You may also categorize by endpoints (e.g. diseases and effects) and exposure (e.g. routes and pathways -- oral ingestion, inhalation, dermal, etc. and drinking water, indoor and outdoor air, soil, food). I suggest that you start making graphics and tables and discuss them. As an engineer, I find that starting with the "picture" and discussing it is not only a good pedagogy, but also a good writing technique. In fact, you may want to record your discussions about each graphic and use these as first drafts of sections in your book chapter. It would make for a more conversational style and might show you where there are gaps and duplications in what you really want to say.

Thank you Dr. Lucas and Dr. Vallero I took your advise and have finally finished my first book chapter and submitted it. I ended up combining organizing according to analysis method and graphics. I will surely use these techniques in writing my project proposal too.